本文選題：重力供液 + 蒸發(fā)器面積��； 參考：《天津商業(yè)大學(xué)》2014年碩士論文

【摘要】：重力供液制冷在制冷行業(yè)中占有重要的地位，重力供液制冷是以熱虹吸為原理的。在重力供液制冷系統(tǒng)中，供液方式為超倍供液，該供液方式能夠使蒸發(fā)器中制冷劑的供液量大于蒸發(fā)器自身的蒸發(fā)量。在蒸發(fā)器中由于制冷劑的供液量大于蒸發(fā)量，保證了蒸發(fā)器管內(nèi)始終保持充分的潤(rùn)濕狀態(tài)，提高了制冷劑在蒸發(fā)器管內(nèi)的流速，從而強(qiáng)化了制冷劑側(cè)的對(duì)流換熱，提高了蒸發(fā)器的換熱效率。 蒸發(fā)器是制冷系統(tǒng)的重要組成部分，提高蒸發(fā)器的換熱效率對(duì)制冷系統(tǒng)來(lái)說(shuō)有著非常重要的作用。蒸發(fā)器的換熱效率主要與傳熱系數(shù)和傳熱溫差相關(guān)。因此，可以通過(guò)增大蒸發(fā)器的傳熱系數(shù)和傳熱溫差來(lái)提高蒸發(fā)器的換熱效率。增大蒸發(fā)器的傳熱系數(shù)主要從兩個(gè)方面入手：一個(gè)是管內(nèi)制冷劑側(cè)，另一個(gè)是管外空氣側(cè)。提高蒸發(fā)器管內(nèi)制冷劑的流速也能提高蒸發(fā)器的換熱效率。 對(duì)重力供液制冷系統(tǒng)中的蒸發(fā)器建立數(shù)學(xué)模型，并且對(duì)其進(jìn)行仿真模擬計(jì)算。本課題是通過(guò)減小蒸發(fā)器的面積來(lái)達(dá)到增大蒸發(fā)器的傳熱系數(shù)和傳熱溫差的目的，為了選擇出與實(shí)驗(yàn)所用冷庫(kù)所匹配的蒸發(fā)器，，因此在仿真模擬中對(duì)五種不同面積的蒸發(fā)器進(jìn)行了模擬研究，這五種蒸發(fā)器面積是以原蒸發(fā)器面積為基礎(chǔ)的，分別為原來(lái)的90%、85%、80%、75%、70%。通過(guò)仿真模擬選擇出最適合實(shí)驗(yàn)所用冷庫(kù)的蒸發(fā)器，并將該蒸發(fā)器加工出來(lái)，運(yùn)用到重力供液制冷系統(tǒng)中，通過(guò)對(duì)其進(jìn)行實(shí)驗(yàn)研究，并且將實(shí)驗(yàn)結(jié)果與仿真模擬出來(lái)的結(jié)果進(jìn)行對(duì)比分析，通過(guò)分析得出選用的蒸發(fā)器面積為原蒸發(fā)器面積的75%的蒸發(fā)器與實(shí)驗(yàn)所用冷庫(kù)最匹配。 在本實(shí)驗(yàn)中，分別進(jìn)行了原蒸發(fā)器與新蒸發(fā)器的實(shí)驗(yàn)對(duì)比，新蒸發(fā)器的仿真模擬與實(shí)驗(yàn)結(jié)果的對(duì)比，新蒸發(fā)器在不同供液高度情況下的實(shí)驗(yàn)對(duì)比和新蒸發(fā)器內(nèi)部溫度場(chǎng)的實(shí)驗(yàn)。通過(guò)對(duì)比實(shí)驗(yàn)得出減小面積后的蒸發(fā)器的傳熱系數(shù)和傳熱溫差都相應(yīng)增大；仿真模擬結(jié)果與實(shí)驗(yàn)結(jié)果相似，可以表明該仿真模擬能夠?qū)χ亓┮褐评湎到y(tǒng)的蒸發(fā)器進(jìn)行預(yù)測(cè)和指導(dǎo)；最適合該重力供液制冷系統(tǒng)的供液高度為900mm；蒸發(fā)器內(nèi)部溫度場(chǎng)分布均勻性有待進(jìn)一步提高。
[Abstract]:Gravity liquid cooling plays an important role in refrigeration industry. Gravity liquid supply refrigeration is based on thermosyphon. In the gravity liquid supply refrigeration system, the liquid supply mode is super multiple, which can make the refrigerant supply in the evaporator larger than that in the evaporator itself. In the evaporator, the refrigerant supply is larger than the evaporator, which ensures the full wetting state in the evaporator pipe, improves the flow rate of the refrigerant in the evaporator tube, and thus strengthens the convection heat transfer on the refrigerant side. The heat transfer efficiency of evaporator is improved. Evaporator is an important part of refrigeration system. Improving the heat transfer efficiency of evaporator plays a very important role in refrigeration system. The heat transfer efficiency of evaporator is mainly related to heat transfer coefficient and heat transfer temperature difference. Therefore, the heat transfer efficiency of evaporator can be improved by increasing the heat transfer coefficient and the difference of heat transfer temperature. Increasing the heat transfer coefficient of evaporator is mainly from two aspects: one is the refrigerant side inside the tube, the other is the air side outside the tube. The heat transfer efficiency of evaporator can also be improved by increasing the flow rate of refrigerant in the evaporator tube. The mathematical model of evaporator in gravity liquid supply refrigeration system is established and simulated. The purpose of this paper is to increase the heat transfer coefficient and heat transfer temperature difference of evaporator by reducing the area of evaporator. Therefore, five kinds of evaporators with different areas are simulated and studied in the simulation. These five evaporator areas are based on the original evaporator area, which are the original 90 pieces of the original evaporator area, and the original 90 pieces of the evaporator area. The evaporator, which is the most suitable for the experiment, is selected by simulation. The evaporator is processed and applied to the gravity liquid supply refrigeration system, and the experimental study is carried out on the evaporator. By comparing the experimental results with the simulated results, it is concluded that the evaporator with 75% of the original evaporator area is the most suitable for the cold storage used in the experiment. In this experiment, the experiments of the original evaporator and the new evaporator, the simulation of the new evaporator and the experimental results, the experimental comparison of the new evaporator under different liquid supply heights and the experiment of the internal temperature field of the new evaporator are carried out respectively. The results show that the heat transfer coefficient and the heat transfer temperature difference of the evaporator with reduced area increase correspondingly, and the simulation results are similar to the experimental results. It can be shown that the simulation can predict and guide the evaporator of the gravity liquid supply refrigeration system, the height of the liquid supply is 900mm, and the uniformity of the temperature field inside the evaporator needs to be further improved.
【學(xué)位授予單位】：天津商業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TB657

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 孫志利;臧潤(rùn)清;;再循環(huán)重力供液制冷系統(tǒng)實(shí)驗(yàn)[J];低溫工程;2008年06期

2 孫艷秀;牛倩倩;;R404A和R507A在雙級(jí)制冷系統(tǒng)中的應(yīng)用分析[J];低溫與超導(dǎo);2010年09期

3 趙小志;臧潤(rùn)清;李星;;再循環(huán)重力供液蒸發(fā)器管內(nèi)換熱性能預(yù)測(cè)[J];低溫與超導(dǎo);2010年12期

4 臧潤(rùn)清;劉琦;李星;;直接供液與重力供液制冷系統(tǒng)的對(duì)比研究[J];低溫與超導(dǎo);2012年02期

5 張春路,丁國(guó)良,李灝;制冷劑飽和熱力性質(zhì)的隱式擬合方法[J];工程熱物理學(xué)報(bào);1999年06期

6 徐傳宙;冷風(fēng)機(jī)蒸發(fā)器的設(shè)計(jì)計(jì)算方法[J];流體工程;1991年09期

7 張春路,于兵,馮寅山,闕雄才,陳芝久;碳?xì)渲评鋭崃π再|(zhì)的快速計(jì)算[J];流體機(jī)械;1997年11期

8 鹿院衛(wèi),王躍社,周芳德;彎管內(nèi)氣液兩相流局部阻力特性研究[J];油氣儲(chǔ)運(yùn);2000年03期

9 盧智利;Chin Soon wee;孫藹軍;李夢(mèng)玲;曹霞;徐巍;莫浩成;胡炎鈞;;R507A，R404A與R22在低溫冷凍工況下的性能比較[J];制冷與空調(diào);2008年S1期

10 項(xiàng)勇;姜寶石;廖全;崔文智;蔡利華;冉啟華;;蒸發(fā)器穩(wěn)態(tài)仿真的一種改進(jìn)算法[J];制冷與空調(diào);2010年02期

本文編號(hào)：1949429